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Questions
What are ambident nucleophiles? Explain with an example.
What do you mean by ambident nucleophiles? Explain with an example.
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Solution
Ambident nucleophiles attack alkyl halides through two distinct atoms. This occurs due to the presence of two nucleophilic centres resulting from resonance structures in the ion. For example, the lone pair of electrons on N in the NO2 ion makes it nucleophilic, while oxygen’s negative charge works as a nucleophile.
Thus, NO2 can attack the O or N atoms, making it ambidentate.
\[\ce{RX + Ag - O - N = O -> \underset{Nitroalkane}{R - NO2}}\]
\[\ce{RX + KNO2 -> \underset{Alkyl nitrate}{R - O - N = O}}\]
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